Cambodia and Thailand on Thursday traded accusations following the escalating situation along the border areas.
Cambodian Prime Minister Hun Manet on Thursday urged the United Nations Security Council to convene an urgent meeting to discuss the matter.
In a letter to Pakistan's permanent representative to the UN Asim Iftikhar Ahmad, whose country assumed the rotating presidency of the Security Council for July, Hun Manet said that since early Thursday, Thai armed forces have launched attacks on Cambodian positions.
The attacks violated fundamental principles of international law, he said.
Hun Manet said Cambodia calls on Thailand to immediately cease all hostilities, withdraw its forces to its side of the border, and refrain from any further provocative actions which could escalate the situation.
On Thursday, Thailand's foreign ministry said the Thai government called on Cambodia to take responsibility for the incidents, cease attacks against civilian and military targets, and stop all actions that violate Thailand's sovereignty.
Otherwise, said the Thai foreign ministry in a statement, the Thai side is prepared to intensify self-defense measures in accordance with international law and relevant principles.
The Thai embassy in Cambodia has urged Thai nationals to leave Cambodia.
The situation escalated following skirmishes which began Thursday morning when Thai and Cambodian troops exchanged fire at a disputed area.